The present invention relates to novel pouring spouts for liquid containers, and also to liquid containers constructed with the novel pouring spout.
Drinkable liquids are typically distributed in containers of variety of designs and shapes, including bottles, laminated cartons and sealed plastic sleeves. Some liquids, such as milk natural juices, wine and many other beverages are distributed in sterile containers, in order to prolong their shelf life. To this end, milk and other beverage containers are treated under high temperature in processes known as pasteurization and Ultra High Temperature (UHT) treatment. Wines are inherently sterile as they typically contain about 14 or more % alcohol in volume, at which concentration of alcohol no life is maintainable.
Liquid containers are provided with a wide variety of pouring spout constructions to enable the liquid contents of the container to be dispensed.
There is a major shared limitation to all existing pouring spouts, as they are all designed and constructed so as to allow air to enter the container upon pouring. Air contains oxygen and typically carries air-born living matter of both prokaryote and eukaryote origin, such as spores and/or mature forms of bacteria, yeast and fungi. Due to this reason, the contact of air with many drinkable liquids, all of which contain organic compounds, results in accelerated spoilage of the liquids. For example, once contaminated with air born living matter, milk spoils within several hours to a few days, depending on the storage temperature. For example, once exposed to oxygen, wine spoils and loses its fine taste.
One popular type of liquid container, commonly used for milk and natural (e.g., orange) juice products, is in the form of a laminated carton integrally formed at its upper end with a gable which may be manually opened by pulling apart its opposite sides to produce a pouring spout. The pouring spout is readily closable by manually returning the opposite sides to their initial condition. The design of this pouring spout permits air to enter to the container upon pouring of the liquid contained therein, thereby significantly decreasing the shelf life of the container contents after once being opened and used. Furthermore, the design of this pouring spout, when re-closed after use, is imperfect and still permits air to enter, thereby further significantly decreasing the shelf life of the container contents after once being opened.
Other containers have more recently been provided with a plastic, tubular pouring spout joined to the gable and normally closed by a screwable cap. However, such a construction not only adds to the costs of producing the containers, but also requires the user to manually remove the cap to permit pouring out the liquid, and to manually reapply the cap in order to reclose the container. Caps sometimes are misplaced when removed. In addition, also this design allows air to enter the container upon pouring the liquid therefrom, resulting in accelerated spoilage of the liquid contents.
Still other containers have recently been provided with a pouring spout including a hinged plastic element, used to open and close the container. This design of a pouring spout, similarly to all of the other designs described herein, allows air to enter the container upon pouring the liquid therefrom, resulting in accelerated spoilage of the liquid contents.
There is thus a widely recognized need for, and it would be highly advantageous to have, a pouring spout and a container devoid of the above limitations. In particular, there is a widely recognized need for, and it would be highly advantageous to have, a pouring spout and a container including same which restrict air from entering the container during or following pouring liquid therefrom, which spout and container can be used for successive pourings, yet the contents thereof is prevented from contacting ambient air and hence prevented from accelerated spoilage.
A broad object of the present invention is to provide a pouring spout of a construction which is self-opening when liquid is to be dispensed, and which is self-sealing when liquid is not being dispensed.
Another object of the invention is to provide a pouring spout which can be constructed either as a cap to be applied to an existing container, or as an integral part of the container itself.
A further object of the invention is to provide pouring spouts, and containers including such pouring spouts, of a relatively simple construction which can be produced in volume and at low cost.
Still a further object of the invention is to provide pouring spouts, and containers including such pouring spouts which restrict air from entering the container during or following pouring liquid therefrom through the pouring spout.
Yet a further object of the invention is to provide pouring spouts, and containers including such pouring spouts, which spouts and containers can be used for successive pourings, yet the container""s contents is prevented from contacting ambient air, thereby accelerated spoilage is prevented.
Hence, according to one aspect of the present invention, there is provided a pouring spout for a liquid container, the pouring spout comprising a pliable plastic sheet defining one side of the pouring spout and movable towards and away from an opposite side of the pouring spout to close and open the pouring spout for dispensing liquid therethrough; the pliable plastic sheet being dimensioned such that when liquid is to be dispensed, the pliable plastic sheet is freely movable away from the opposite side by the liquid to permit the liquid to be dispensed therethrough, and when liquid is not being dispensed through the pouring spout, the pliable plastic sheet moves towards and into contact with the opposite side and adheres thereto by surface tension to produce a self-sealing action with respect to the pouring spout.
As will be described more particularly below, such a self-sealing pouring spout may be applied to various types of products normally refrigerated to prolong their life after the containers have been opened. In addition, such a pouring spout may also be used to prolong the storage life of non-refrigerated products after opening.
A number of embodiments of the invention are described below for purposes of example. In some described embodiments, the opposite side of the pouring spout is defined by another pliable sheet, whereas in other described embodiments, the opposite side of the pouring spout is a rigid member.
Where the opposite side of the pouring spout is another pliable sheet, the longitudinal edges along the opposite sides of the two pliable sheets should be joined together to define a passageway for dispensing the liquid, but one or both of the longitudinal edges of the two pliable sheets should be free to move to allow the passageway to open when dispensing a liquid, and to be self-closing (and self-sealing) when not dispensing the liquid. If both longitudinal edges are secured, e.g., to an enclosing tube, the pliable sheets should be elastic to allow the opening and self-closing of the dispensing passageway.
On the other hand, when the opposite side of the pouring spout is rigid, it is preferably non-planar, i.e., concave, to allow the self-opening and self-closing of the passageway by the displacement of the pliable sheet toward and away from that rigid surface.
In some described embodiments, the pouring spout is in the form of a cap removably attachable to a liquid container. In other described embodiments, the pouring spout is initially fixed to, or integrally formed with, the liquid container in alignment with an opening therein.
The invention also provides a number of liquid container constructions including such pouring spouts. In one described construction, the liquid compartment of the container is also of pliable plastic sheets which are integrally formed with the pliable plastic sheets of the pouring spout. In other described embodiments, the container is of a rigid construction and includes a filtered air inlet into its liquid compartment to permit dispensing substantially the complete liquid contents of the container through the pouring spout. Still other embodiments are described in which the container is of a construction permitting the internal volume of its liquid compartment to be reduced as liquid is dispensed therefrom.
According to a further described embodiment, the container may also include a manually-movable pressure member for pressing the pliable plastic sheet of the pouring spout to its closed position in contact with the opposite surface. The present invention successfully addresses the shortcomings of the presently known configurations by providing a pouring spout and a container including same which restrict air from entering the container during or following pouring liquid therefrom, which spout and container can be used for successive pourings, yet the contents thereof is prevented from contacting ambient air and hence prevented from accelerated spoilage.
Further features and advantages of the invention will be apparent from the description below.